A large Canadian beef recall has affected Cargill Inc. and has spread this week to several hundred U.S. supermarkets, including five Minnesota Wal-Marts and over 110 Western grocery stores owned by Supervalu.

The beef in question originated from Edmonton, Alberta-based XL Foods, one of Canada's largest meat processors, and some of it was sold to Cargill. The Canadian Food Inspection Agency on Sept. 16 announced a recall, which has been expanded several times to include over 250 products at major grocery chains throughout Canada.

The growing recall is emblematic of an underlying ground beef safety issue. Beef trim -- leftovers from cutting steaks, roasts and the like -- are routinely bought and sold among beef processors to make hamburger.

So, when a problem arises at one beef trim producer, it can easily spread through the ground beef supply chain.

The recall reportedly has been linked to eight cases of E. coli O157:H7 in Alberta, including a young girl who was hospitalized. There have been no deaths in Canada, and no reports of illness in the United States, but E. coli can cause serious stomach ailments and sometimes kidney failure.

The U.S. Department of Agriculture estimates that so far, over 800,000 pounds of XL beef products shipped to the United States are linked to the Canadian recall. The USDA on Sept. 20 issued a "public health alert," which has led several U.S. retailers to remove ground beef linked to XL.

The USDA has listed 316 retail outlets that are effected, but that may grow. Wal-Mart alone has pulled XL-related beef products from over 300 of its stores in 40 states, said Dianna Gee, a company spokeswoman.

Minnetonka-based Cargill, one of North America's largest beef processors, bought beef trim from XL that was linked to the Canadian recall. That trim was used in Cargill products sold to a Canadian retailer as well as to a "handful" of U.S. food service customers, said Mike Martin, a Cargill spokesman.

Cargill declined to name the customers. The firm is working closely with its U.S. food service customers to "manage the situation" and keep recall-impacted beef out of circulation, Martin said.

Martin said the "vast majority" of beef products bound for the Canadian retailer didn't get into commerce. They were mostly held in inventory at retailers or at Cargill facilities, he said. Canadian retailers have worked with XL to recall beef that was on store shelves.

No Cargill retail beef products in the United States were effected by the XL recall, Martin said.

While Cargill produces plenty of beef trim from its own cattle slaughter and processing operations, it also buys trim from other beef companies, a common practice.

Numerous beef processors in Canada and the U.S. buy trim from XL, Martin said. "It was an XL recall, but unfortunately it spread through a lot of other companies."

Bill Marler, a Seattle lawyer who specializes in food safety cases, said such recalls are endemic to hamburger production. "If you have trim that tests positive [for pathogens], it goes into so many products. [The problem] gets amplified really quickly."

USDA discovered the problem

The USDA did a routine test of XL product on Sept. 3, and it came up positive for E. coli O157:H7. It then notified Canadian food safety regulators and both agencies launched an investigation.

Wal-Mart pulled ground beef subject to the alert last weekend, Gee said. Nationwide, ground beef trays, chubs and patties were effected at Wal-Mart stores, but only frozen patties in its Minnesota outlets, she said.

Albertsons, which is owned by Eden Prairie-based Supervalu, on Monday announced a recall of ground beef products imported from XL and sold at all of its stores in Washington and Oregon, as well as three outlets in Idaho.

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